The WHAT?! That was my reaction when my wife and I were chatting about the next project that I should work on with my AirWolf3D printer. She was talking about how it is tough to find a good transilluminator for her job as a NICU nurse. To assist with starting IVs on small babies, which is most of what she sees in the NICU, she needs a high-powered LED light that can show her the baby's veins while attempting to insert the needle. Let's just say that I'm happy I'm not in the medical field- not afraid of needles, but I'm not about to attempt finding the vein on a kid who's 1 day old and 3 pounds. Nooooooo thank you.

For only $119, you can... WHAT?! That much money? Why? Well, when you think about keeping your nursing license, that's a pretty small price to pay, but it's still a ton of cash for a cool red flashlight. This got us thinking about a project for students. Almost every town has a hospital with a pediatric unit, and many have NICU units as well. Nurses in those fields love kids, and we are quite certain that they would love a free transilluminator created by students. Therefore, using the 3D printer and some hardware bought at Radio Shack, I put one together.

The easy part was, well, nothing really. This was a tough design because everything had to be precise. The compartment for the 9 volt battery needed to have specific dimensions, which I had to change to account for the stuffing of wires, the cap for the 9V lead, and the resistor. The hole for the push button switch needed to be exact so that it didn't float around too much or wouldn't fit in the first place. The same went for the LED light, and that was crucial because it is truly what makes or breaks the project.

During this whole design, I went through it like I think many students would. I eyeballed the majority of the measurements, then slowly started realizing how precise each measurement needed to be. Everything is mocked up to fit snug but not restricting, and it printed exactly like I needed it to.

The fun part, aside from designing and printing in what still seems like magic, was doing the electrical. I haven't done circuit work since my days in college as a physics student, so this was an absolute blast (and challenge... a big challenge. More on that later). Using a soldering kit, I was able to hook the battery to the switch to the resistor to the LED light. This is magic to me and I'm totally digging it.

Unfortunately, it didn't go as planned (no surprise there). It started out just fine, working like it's supposed to, so I took it inside, showed my wife, and we had a little lunch. During lunch, the battery started popping. I quickly unplugged it and realized that it was overheating. There was a cross-up somewhere in the circuit, but I couldn't see it. After lunch, the switch got unscrewed and my problem was revealed. As I was screwing in the switch, the positive and negative wires had tangled, causing a short. After re-taping them and screwing the switch in more carefully, it worked just fine.

After printing finished and I got the casing cleaned up, which took a little bit of time due to the smoothness required to fend off the harboring of bacteria in the NICU, I tested out the switch and was happy with the result. A pretty sweet addition to this was having my 4 year-old work with the soldering gun and actually help with some of the assembly. No need, I was there the whole time to make sure the only hands that would be damaged were my own.

I love being a dad

Finished product before the 320-grain sanding to clean it up

I still have a lot to learn, but getting to work with circuits has quickly become a fun side project.

Also, a huge thank you to Frank Noschese once again for lending a hand to a guy who got in over his head with some garage work circuit-building. It's nice to have people I can reach out to without the fear of feeling like a fool.

@Jstevens009 If you want it to last longer, use 2 C or D batteries. Or 4 AAs: 2 in series (3V) in parallel with another 2 in series.

So, what did I learn for this lesson? First of all, precision is everything. I was fortunate enough to take my time with the measurements and have them all fit within a reasonable margin of error. The whole "measure twice, cut once" mantra holds true and tends to punch me in the face during projects. For this one, though, I'm happy to say that I avoided failure on that front.

Second, do all research thoroughly. I looked into how to create a circuit, then went to Radio Shack and had them hook me up. I took the advice of a guy at the store and just ran with it. Bad idea. Next time, I'll due better groundwork and not just trust the word of someone I don't know. Come to find out, the 9-Volt option is one of the worst ones I could've chosen.

Third, be willing to take a risk. Matt Vaudrey and I bring this up all the time in our trainings, but it's so true. I stuck my neck pretty far outside of what I'm capable of and just went for it. Sure, I had the support of others, but that's what this whole learning thing is all about anyways, isn't it? It was so much fun learning about topics and being refreshed on others. That's how people live into their later years, or so I hear, by continuing to give their brains exercise.

The whole time I'm doing this, I can't help but think about the intensity that would be going on in the classroom as they scramble, stumble and succeed in putting something like this together, then donating it to the local NICU to continue building the connection between school and community. Now my wife gets to take this to work and give me some real life R&D feedback!

I really enjoyed reading the research you did and perseverance it took. I am going to dig a little deeper into the 3D printing world this year and it was nice to read about something like this. Also, I didn't know we both had wives that are nurses! Awesome.